Archive
003
EXH-0031998Fictional reconstruction

The 26th of April

April 1998. A student in Taiwan ships a parasitic .exe. It lies dormant until Chernobyl's anniversary, then it overwrites the flash BIOS on thousands of PCs.

Type
Classic
Difficulty
Beginner
Era
1990s
Time
8 min

Briefing

A floppy arrived with cracked games. One binary is `CIH.EXE`, parasitic, infects other PE headers, no mass mailer. The scary part is what happens on a specific calendar day. You have strings and a disassembler summary, not a live infected machine.

Your role

AV analyst reconstructing a submitted sample flagged by a reseller in Seoul.

Objective

Identify the payload class, its trigger date, and why antivirus heuristics called it CIH / Chernobyl.

Terminal environment

user
analyst
host
iso-pc
cwd
/home/analyst
steps
3
Enter the terminalAbout 8 minutesSafe simulation

Safety note. This is a safe reconstruction. All systems, files, hosts, credentials, and outputs are simulated. Do not use these techniques on systems you do not own or have explicit permission to test.